U.S. Environmental Protection Agency. Principles of design and operations of wastewater treatment pond systems for plant operators, engineers, and managers.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)U.S. Environmental Protection Agency. Principles of Design and Operations of Wastewater Treatment Pond Systems for Plant Operators, Engineers, and Managers.
توثيق جمعية اللغة المعاصرة MLA (الإصدار التاسع)U.S. Environmental Protection Agency. Principles of Design and Operations of Wastewater Treatment Pond Systems for Plant Operators, Engineers, and Managers.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.